---
pageClass: is-wide-page
---

# LogMessage (UORB message)

A logging message, output with PX4_WARN, PX4_ERR, PX4_INFO.

**TOPICS:** log_message

## Fields

| Name      | Type        | Unit [Frame] | Range/Enum | Description                                              |
| --------- | ----------- | ------------ | ---------- | -------------------------------------------------------- |
| timestamp | `uint64`    |              |            | time since system start (microseconds)                   |
| severity  | `uint8`     |              |            | log level (same as in the linux kernel, starting with 0) |
| text      | `char[127]` |              |            |

## Constants

| Name                                            | Type    | Value | Description |
| ----------------------------------------------- | ------- | ----- | ----------- |
| <a id="#ORB_QUEUE_LENGTH"></a> ORB_QUEUE_LENGTH | `uint8` | 4     |

## Source Message

[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/LogMessage.msg)

::: details Click here to see original file

```c
# A logging message, output with PX4_WARN, PX4_ERR, PX4_INFO

uint64 timestamp		# time since system start (microseconds)

uint8 severity # log level (same as in the linux kernel, starting with 0)
char[127] text

uint8 ORB_QUEUE_LENGTH = 4
```

:::